Muscles of the Lower Limb Dr. Emad I Shaqoura IUG Faculty of Medicine

Thigh: anterior & medial aspects: Cutaneous Nerves: The lateral cutaneous nerve of the thigh, a branch of the lumbar plexus (L2 and 3), enters the thigh behind the lateral end of the inguinal ligament Femoral branch of the genitofemoral nerve Ilioinguinal nerve Medial cutaneous nerve of the thigh Intermediate cutaneous nerve of the thigh

Superficial Veins The great saphenous vein: ascends in the medial side in company with the saphenous nerve and passes behind the knee and curves forward around the medial side of the thigh. It passes through the lower part of the saphenous opening in the deep fascia and joins the femoral vein about 1.5 in. (4 cm) below and lateral to the pubic tubercle It receives three tributaries: the superficial circumflex iliac vein, the superficial epigastric vein, and the superficial external pudendal vein

Superficial Veins Small saphenous vein: arises from the lateral part of the dorsal venous arch of the foot (Fig. 10-19). It ascends behind the lateral malleolus in company with the sural nerve. It runs up the middle of the back of the leg. The vein pierces the deep fascia and passes between the two heads of the gastrocnemius muscle in the lower part of the popliteal fossa. It ends in the popliteal vein.

Inguinal Lymph Nodes Superficial Inguinal Lymph Nodes: The superficial nodes lie in the superficial fascia below the inguinal ligament and can be divided into a horizontal and a vertical group Deep Inguinal Lymph Nodes: The deep nodes are located beneath the deep fascia and lie along the medial side of the femoral vein

Superficial & Deep Fascia of the Thigh: Superficial Fascia of the Thigh : fatty layer of the superficial fascia. Deep Fascia of the Thigh (Fascia Lata): encloses the thigh like a trouser leg and at its upper end is attached to the pelvis and the inguinal ligament. On its lateral aspect, it is thickened to form the iliotibial tract , which is attached above to the iliac tubercle and below to the lateral condyle of the tibia. saphenous opening is a gap in the deep fascia in the front of the thigh just below the inguinal ligament. It transmits the great saphenous vein, some small branches of the femoral artery, and lymph vessels. saphenous opening is a gap in the deep fascia in the front of the thigh just below the inguinal ligament. It transmits the great saphenous vein, some small branches of the femoral artery, and lymph vessels

Fascial Compartments of the Thigh: Three fascial septa pass from the inner aspect of the deep fascial sheath of the thigh to the linea aspera of the femur: The compartments are anterior, medial, and posterior in position. Contents of the Anterior Fascial Compartment of the Thigh: Muscles: Sartorius, iliacus, psoas, pectineus, and quadriceps femoris Blood supply: Femoral artery Nerve supply: Femoral nerve

Femoral Triangle It is a triangular depressed area situated in the upper part of the medial aspect of the thigh just below the inguinal ligament. Its boundaries are as follows: Superiorly: The inguinal ligament. Laterally: The sartorius muscle. Medially: The adductor longus muscle. Its floor is gutter shaped and formed from lateral to medial by the iliopsoas, the pectineus, and the adductor longus. Its roof is formed by the skin and fasciae of the thigh. The femoral triangle contains the terminal part of the femoral nerve and its branches, the femoral sheath, the femoral artery and its branches, the femoral vein and its tributaries, and the deep inguinal lymph nodes.

Adductor (sub-sartorial) Canal It is an intermuscular cleft situated on the medial aspect of the middle third of the thigh beneath the sartorius muscle. It commences above at the apex of the femoral triangle and ends below at the opening in the adductor magnus. The antero-medial wall is formed by the sartorius muscle and fascia. The posterior wall is formed by the adductor longus and magnus. The lateral wall is formed by the vastus medialis. The adductor canal contains the terminal part of the femoral artery, the femoral vein, the deep lymph vessels, the saphenous nerve, the nerve to the vastus medialis, and the terminal part of the obturator nerve.

Muscles of the Gluteal Region:

Foramina of the Gluteal Region Greater Sciatic Foramen: is formed by the greater sciatic notch of the hip bone and the sacrotuberous and sacrospinous ligaments. It provides an exit from the pelvis into the gluteal region. The following structures exit the foramen: Piriformis, Sciatic nerve, Posterior cutaneous nerve of the thigh, Superior and inferior gluteal nerves, Nerves to the obturator internus and quadratus femoris, Pudendal nerve, Superior and inferior gluteal arteries and veins, Internal pudendal artery and vein. Lesser Sciatic Foramen: is formed by the lesser sciatic notch of the hip bone and the sacrotuberous and sacrospinous ligaments. It provides an entrance into the perineum from the gluteal region. Its presence enables nerves and blood vessels that have left the pelvis through the greater sciatic foramen above the pelvic floor to enter the perineum below the pelvic floor. The following structures pass through the foramen: Tendon of obturator internus muscle,Nerve to obturator internus,Pudendal nerve,Internal pudendal artery and vein

Popliteal Fossa The popliteal fossa is a diamond-shaped intermuscular space situated at the back of the knee. It contains the popliteal vessels, the small saphenous vein, the common peroneal and tibial nerves, the posterior cutaneous nerve of the thigh, the genicular branch of the obturator nerve, connective tissue, and lymph nodes. Boundaries: Laterally: The biceps femoris above and the lateral head of the gastrocnemius and plantaris below. Medially: The semimembranosus and semitendinosus above and the medial head of the gastrocnemius below. The anterior wall or floor is formed by the popliteal surface of the femur, the posterior ligament of the knee joint, and the popliteus muscle. The roof is formed by skin, superficial fascia, and the deep fascia of the thigh.

Lateral Compartment of the leg:

Posterior compartment of leg: Muscles in the posterior (flexor) compartment of leg are organized into two groups, superficial and deep, separated by a layer of deep fascia. Generally, the muscles mainly plantarflex and invert the foot and flex the toes. All are innervated by the tibial nerve. The superficial group comprises three muscles-gastrocnemius, plantaris, and soleus -all of which insert onto the heel (calcaneus) of the foot and plantarflex the foot at the ankle joint. They propel the body forward off the planted foot during walking and can elevate the body upwards onto the toes when standing. Two of the muscles (gastrocnemius and plantaris) originate on the distal end of the femur so can also flex the knee. The gastrocnemius muscle is the most superficial of the muscles in the posterior compartment and is one of the largest muscles in the leg. It originates by two heads, one lateral and one medial: the medial head is attached to the posterior aspect of the distal femur just behind the adductor tubercle and above the articular surface of the medial condyle; the lateral head originates from a facet on the upper lateral surface of the lateral femoral condyle where it joins the lateral supracondylar line.

Table 6-7. Deep group of muscles in the posterior compartment of leg (spinal segments in bold are the major segments innervating the muscle) Body_ID: None Function Innervation Insertion Origin Muscle Body_ID: T006007.50 Unlocks knee joint (laterally rotates femur on fixed tibia) Tibial nerve [L4 to S1] Lateral femoral condyle Posterior surface of proximal tibia Popliteus Body_ID: T006007.100 Flexes great toe Tibial nerve [S2,S3] Plantar surface of distal phalanx of great toe Posterior surface of fibula and adjacent interosseous membrane Flexor hallucis longus Body_ID: T006007.150 Flexes lateral four toes Plantar surfaces of bases of distal phalanges of the lateral four toes Medial side of posterior surface of the tibia Flexor digitorum longus Body_ID: T006007.200 Inversion and plantarflexion of foot; support of medial arch of foot during walking Tibial nerve [L4,L5] Mainly to tuberosity of navicular and adjacent region of medial cuneiform Posterior surfaces of interosseous membrane and adjacent regions of tibia and fibula Tibialis posterior Body_ID: T006007.250